The 44-year-old actress plays Detective Stella Gibson in the BBC police drama, which follows her hunt for a serial killer, and she was especially drawn to how forward her character is when it comes to getting what she wants.

She said: ''If [Stella] finds someone attractive, she has the balls to say, 'Hey, you know ... come on', which I like in a woman. That's a really, really cool thing.

''But I also like the fact there are consequences to that, which you see in the series. She's definitely my most sexually confident role. I've played a lot of tightly wound, dark, miserable, confused, suicidal women.''

While the former 'X Files' actress admires her alter ego's confidence, she admits there is little common ground between her actual self and her character.

Gillian added: ''I haven't quite figured out exactly why she appeals to me so much. It can't be that we are similar. Even if it was true, I'm not sure if I could admit to it.

''She's much more reserved than I am and feels more mature, grown up and worthy of the responsibility that's laid down before her, whereas I wouldn't be in any way, shape or form. I'm definitely naughty and silly and goofy and ridiculous.''